(a) Field of the Invention:
This invention relates to a container and also to a filled container. Described more specifically, this invention is concerned with a container for holding plural contents as individually separate items, especially to a container for permitting mixing of plural contents, which have been hermetically sealed in mutually-isolated plural compartments, immediately before use without opening the container, namely, without exposing the contents to the surrounding atmosphere. This invention also pertains to a similar container filled with contents.
(b) Description of the Related Art:
There has conventionally been a strong demand for containers adapted to mix two or more substances, e.g., medicinal and pharmaceutical substances of different kinds in a hermetically-sealed state immediately before use. This demand is particularly strong, for example, for warming or cooling media using reaction heat to be produced upon mixing two or more kinds of substances, foods and medicinal and pharmaceutical substances containing two or more substances which must be mixed immediately before use because of their modifications or deterioration along the passage of time when stored or processed as a mixture, and like products.
Namely, there are many medicinal and pharmaceutical substances which are susceptible to deterioration when stored or processed as a mixture, for example, to thermal deterioration when subjected to sterilization in an autoclave, or to modifications upon standing. In addition, mixing of two or more medicinal and pharmaceutical substances in a hospital involves a potential danger that they may be contaminated upon mixing. Prevention of such contamination requires a complex operation. This may lead to an operational error. There has hence been a demand for containers which permit mixing of two or more medicinal and pharmaceutical substances by a simple operation and moreover in a completely closed system immediately before use.
For example, high-calorie transfusion solutions are used for intravenous hyperalimentation (IVH) therapy which is applied widely in recent years. It is essential for such transfusion solutions to contain suitable amounts of all nutrients required for the human body. Namely, they are multi-component transfusion solutions containing sugars, amino acids, principal electrolytes, trace metals, vitamins, etc. Under the circumstances, it is however impossible to prepare each transfusion solution as a single composite solution containing all the ingredients in view of their mutual compatibility, their stability in the course of the preparation of the transfusion solution and the stability of the transfusion solution upon standing. For example, when glucose and amino acids are mixed and sealed as a single-pack liquid preparation in a container, reactions take place between the glucose and amino acids upon autoclave sterilization or during storage so that the thus-prepared transfusion solution may be colored or modified. Under the circumstances, several drug solutions marketed separately are mixed upon or before administration. This however requires a complex operation and thus involves a potential danger of dispensing error. Further, this does not enable mixing of the drug solutions in a completely closed system and is therefore not satisfactory from the standpoint of safety against hospital infection. For these reasons, there is an outstanding desire for the development of containers which permit mixing of two or more medicinal and pharmaceutical substances by a simple operation and in a completely closed system.
Recently, some drug preparations are available in containers with a means of isolation provided internally. The isolation means is broken or otherwise opened immediately before use, so that the ingredients of each drug preparation can be mixed within its container. Conventional isolation means include a plug fixed in each partition dividing a container into plural compartments so that the plug is broken from the outside of the container to communicate the compartments to each other upon use. As an alternative, each partition dividing a container into plural compartments is formed partly open and the open portion of the partition is externally closed by a clip. The former isolation means, namely, the plug system however requires the insertion of a separately-formed plug into a container and then its bonding to the container. This operation however has a high risk of contamination of the interior of the container. Furthermore, it is difficult to hermetically bond the plug and container. For the bonding of the plug and container, high-frequency welding is suitable because it can easily establish bonding of a three-dimensional structure. However, materials which can be bonded by high-frequency welding are limited to those having a large dielectric loss such as polyvinyl chloride resin and ethylene-vinyl acetate copolymer. Polyolefin resins which assure a high degree of safety have a small dielectric loss, so that they cannot be used. On the other hand, the latter isolation means, namely, the clip system does not allow one to find out whether the partition has been opened or not in the course of transportation or storage. This leads to significant uneasiness and concern by the user. To ensure the isolation, it is also necessary to form the open portion as small as possible. This however leads to another requirement that when plural medicinal and pharmaceutical substances are mixed, they must be put together in a large mixing compartment. As a result, there is a further problem that the overall size of the container becomes greater.